The present invention relates to apparatus for carbonating liquids and more particularly to carbonating a beverage in a container from which it will be served.
Home carbonation apparatus is well-known in the art. They come in many different forms. A common characteristic of home carbonation systems, as this term is used in the present specification, is that liquid is introduced into a vessel from which it will be served and carbonated in that vessel. Such serving vessels comprise types of containers most commonly known as seltzer bottles and soda bottles. Vessels are distinguished from dispensers in the present description in that a dispenser is normally stationary and kept in the same place and spatial orientation whether in the process of storing or dispensing. Home carbonation implies that the vessel in which liquid being carbonated is of a conveniently handled size corresponding to common nominal sizes in which carbonated beverages for providing multiple servings are usually sold. These sizes range primarily from 28 fluid ounces to one liter (33.4 fluid ounces).
Simpler forms of home carbonation apparatus use the well-known single charge CO.sub.2 gas cartridge commonly available in hardware stores having a tube of CO.sub.2 closed in a tube with a puncturable metal seal. The apparatus comprises means for holding the cartridge and for breaking the seal with a pointed end of a tube communicating with means to discharge the CO.sub.2 into the vessel and then disposing of the cartridge. An example of such a system for carbonating in a soda bottle is disclosed in U.S. Pat. No. 2,805,846 to L. Dewan issued Sept. 10, 1957. Many other single charge cartridge systems have also been provided in the context of a seltzer bottle. Only one vessel full of liquid is carbonated per operation of installation in the system of a carbon dioxide source.
Increasing sophistication in home carbonation systems has led to the use of a more substantial CO.sub.2 gas canister with the capacity for carbonating many vessels full, for example two hundred, of liquid. Such a container is conveniently usable at home and could weigh as little as eight pounds. Nominal dimensions are a diameter of seven inches and a height of eighteen inches. In a home apparatus using such a canister, a base is provided for individual connection of a canister thereto and for readily releasable engagement of a vessel therewith. An example of such a system in the prior art is disclosed in U.S. Pat. No. 4,481,986 issued Nov. 13, 1984.
In such a system, a CO.sub.2 canister is inverted and supported to the base. Valve means communicate CO.sub.2 from the canister and an inlet to a fluid path in the base. CO.sub.2 outlet means are provided for injecting CO.sub.2 into a vessel. Further valve means control flow from inlet to the outlet. The outlet means include a vertically disposed, hollow, needle-like nozzle opened at an upper end having a gas path along a vertical axis and allowing gas to escape at an upper end thereof into the vessel. The system uses a vessel sized for cooperation therewith. The vessel is closed with a cap particularly suited for use in the system. The cap is elastomeric and normally seals the vessel. However, it will admit to penetration thereby of the nozzle and reseal after the nozzle is withdrawn therefrom. In use, liquid is placed in the vessel which is sealed with the cap. The vessel is then inverted and brought into engagement with the system. More specifically, the cap is pressed onto the vertically extending nozzle and the vessel is lowered to be supported to the base. The nozzle extends through the cap and into the liquid. The further valve means are opened and the liquid is carbonated. Suitable pressure regulating means provide for proper pressurization. The further valve means are closed, and the vessel is removed from engagement with the system.
In such a system, it is desirable to maximize the carbonation achieved for the pressure level utilized since pressure must be limited to a level below that which can be safely handled by the vessel. Other factors that will increase carbonation are water temperature and surface contact. Water temperature cannot be lowered below the freezing point. The present invention deals with the dispersion of gas in water or other liquid in this sort of system.